The invention generally relates to forming systems for constructing structures of a variety of shapes and sizes using concrete or other pourable, hardenable materials. The invention more specifically relates to a system for the use of rigid panels as forms for constructing such structures, including systems where the panels remain on the formed structure.
An important technique for the construction of durable structures utilizes pourable, hardenable materials to provide structural elements, such as foundations, walls, pillars, beams, floors and similar structural elements. The most common materials used in such techniques are various forms of cementitious concrete. Cements and concretes generally are readily available, cost effective, provide advantageous structural characteristics, can be adapted for a variety of uses and applications, and are well known in the construction field.
The use of cements and concretes as structural building materials further provides many advantages over other building materials. For example, concrete foundations, walls, floors, pillars and beams, structural elements, etc. generally are considered resistant to adverse weather conditions, such as high winds and heavy rains, fire damage, insect damage, fungus damage, mildew damage, and. moisture induced rot damage. Furthermore, cement and concrete structural elements, under most conditions, are very durable and can be used to form structures that provide superior stress and weight bearing properties in a variety of building designs. Concrete materials further may be formed into a wide variety of shapes, forms, applications, and structural elements. This flexibility in use largely is due to the ability to install cement and concrete materials in a liquid, semi-liquid, or slurry state into a forming system where the materials harden and cure in place to form a permanent shape or element. Moreover, a wide variety of reinforcing elements may be incorporated in the concrete structure, including metal bars, mesh, metal and plastic fibers, pre- and post tensioning systems, etc.
In one important and frequent use of cement and concrete materials, a concrete slurry is used to provide pre-formed or formed in place elements in a variety of building structures such as foundations, building walls and building floors. In such applications, a set of opposing forms are provided and installed at the work site in a desired configuration. Sufficient spacing is allowed between the sets of forms to provide a cavity that is filled with concrete or with other cementitious materials. The forms are commonly made of wood, metal or a combination of such materials. It also is common to place reinforcing metal bars or mesh between the forms at various locations which are then embedded in the concrete or cementitious materials to strengthen the resulting structure.
In such systems, the forms maintain their proper position by a combination of metal tie plates between adjacent forms and metal tie rods between opposing forms. Such tie systems hold the forms in place during the assembly of the forming system and resist the movement of the forms from their proper alignment positions when concrete or other cementitious materials are poured and worked between the forms. After the concrete or other materials are hardened and at least partially cured, the conventional forms are typically removed from the structures and reused in other installations.
As an alternative to conventional forming systems, there is considerable interest in the use of forming systems utilizing pre-formed, expanded polymeric foam forms, which are often referred to as Insulating Concrete Form or xe2x80x9cICFxe2x80x9d systems, to replace conventional wood and metal forms. Many ICF forming systems use forms made of blocks and panels molded or manufactured from low density polymeric foam materials and are retained as permanent or semi-permanent components of the completed structure.
The blocks and/or panels that are left in place after the concrete hardens provide substantially enhanced insulating characteristics for the structure, reduce moisture passage through the structure walls, provide a substrate into which utility lines and piping can be installed, provide a surface for the attachment of finishes and provide other related benefits. As a result, ICF systems offer the possible use of concrete or other hardenable materials in building foundations and in above-ground walls of buildings or other structures. Thus, ICF systems have applications in residential, commercial and governmental building projects and programs.
Prior ICF systems utilizing insulating foam forms, however, possessed disadvantages that reduced their effectiveness in many building construction applications. Forming systems utilizing a hollow block, horizontal panels or other non-standard forms, such as panels or blocks with a gridded surface, typically require special assembly and forming procedures, construction techniques and equipment that are significantly different than those used with conventional forming systems, employing the well known wood and metal forms. In many systems, it is difficult to obtain consistent dimensions in the manufacture of the blocks or other components, and the expense of using the system is increased due to the shape and difficulties in shipping and assembling the forming components.
For example, in some systems, the concrete structures have inconsistent cross-sections, which results in uncertainty concerning the thickness of the concrete and foam panels in substantial portions of the structure. This can be a problem where knowledge of the wall and panel thickness is necessary for attaching structural elements to the formed wall structure, such as wall systems, shelving, floor members etc. The same can be true with systems that employ horizontal panels or blocks of foam materials with cavities in the shape of columns or tubes for receiving concrete or other hardenable materials.
Moreover, corner, door and window openings and other aspects of such systems were necessarily made during assembly or construction of the system, and could not reliably be made in advance offsite or at one time on site.
In some systems, multiple blocks or panels must be stacked on top of each other or side by side and in multiple layers to make wall forms of the same dimensions as forming systems using significantly fewer and larger conventional forms. Such systems using block forms and some horizontal panel systems also frequently encounter difficulties with form floating and compression. In such systems, the lower density of the forms and the higher density of the concrete can result in instances where the forms begin to float on the concrete, separating and permitting leakage through the form seams. This can be a particular problem in the upper sections of wall forms, and can also affect the wall ties, i.e. the wall ties also are urged upward by the concrete creating openings in the wall seams. In other instances, the weight in of the concrete in the system imposes sufficient downward force on the system to compress the foam members changing the wall height and, at times, the spacing between the forms.
As a result, it frequently is necessary to make repeated cuts and adjustments to the forming panels, blocks or similar forms during construction of the forming structure. Such ICF systems, in addition, typically are not familiar to contractors and construction workers and require significant special training or retraining in the use of the system, and the time and labor required for the assembly of such systems can significantly exceed that required for conventional systems.
Many potential users, regulatory agencies and inspectors, in addition, are unfamiliar and reluctant to accept the non-standard forming materials and the additional or unique procedures and equipment required in prior ICF systems. Thus, additional construction, engineering and regulatory considerations typically apply to such systems that are undesirable or unacceptable in many applications.
Nearly all ICF systems, in addition, require the use of specially formed, proprietary foam panels or other such specialized panels with recessed grooves, overlapping joint structures, pre-embedded gripping members or similar features that are necessary to the assembly and function of such systems. As a result, they were xe2x80x9cclosedxe2x80x9d systems and were not suitable for use with generally available generic components, or with use from alternative competitive components. Thus, suppliers and competition among suppliers for the components was reduced limiting cost reductions and wide spread acceptance of the systems.
For example, one approach to developing ICF forming systems requires specially configured, vertical foam panels with slots formed or cut into the panels. These slots must be incorporated in the panel when it is manufactured, or must be added to the panels at the work site. In such systems, the modification of the forms at the work site to accommodate non-standard dimensions, design changes made on site, etc. can require significant additional time and labor to cut and properly align such slots which increases the cost of the system and may hamper such systems"" use as a replacement for conventional forming systems.
In some prior systems, particularly those using horizontal panels, tie elements spanning the ICF panels are used to stabilize the system and hold the forms in a predesired relative position. In some such systems have utilized many individual, tie elements, where multiple tie elements must be installed across each individual set of opposing panels. In other systems, the panels placed on top of channels or H-type channel members, which then require the installation of multiple tie members between opposing channel pieces. In other systems, short rail members are installed between the panels through pre-embedded gripping members.
Prior systems utilizing substantial numbers of individual tie elements typically require significant labor and time to install properly, and may not provide gripping surfaces on the cavity side of the forms. Prior systems using channel members frequently use channels dimensioned to require substantial force to insert the panel edges into the channels, which also increases the labor and expense of using the systems.
In some systems, particularly those using flat panels, the formation of corners, curves and turns in the forming system is a further concern and may require complicated forming and construction techniques. Due to the geometry of various corners and turns, it often is necessary to provide specially designed corner forms that are pre-configured to certain corner shapes. Most prior corner systems also require extensive and heavy bracing and reinforcement in order to maintain the proper alignment and required corner strength.
Moreover, in most systems utilizing flat panel forms, it is very difficult, if not prohibitive, to use such systems to form curves in corners or other wall sections. Similarly, the prior systems frequently were difficult to adapt for use to provide a corner with a range of corner angles and many were useable to form only right angle (90 degree) corners.
Thus, the panels and other form components of other systems required extensive modifications, custom made parts and significant additional engineering and expense, to provide such corners and curves, if they could be produced at all by such systems. As a result, such systems often require the maintenance of significant inventories of the preformed corner sections and additional expense of installing and maintaining the corner bracing. Such limitations reduce the flexibility of the system and materially increases inventory, installation, shipping and storage costs of the systems. Furthermore, if the required corners are not available during the construction of the forming systems, the construction process may be significantly slowed or halted until the corners are available. This could result in considerable additional expense due to idled labor and missed deadlines.
In many prior systems using ICF forms, the various reinforcing and joining structures also create other inefficiencies in the basic structure of the formed and cured concrete materials. For example, in some instances electrical conduit, plumbing and other piping must be installed in or along the foam forms walls. To install such conduit or piping, channels may be cut into the foam panels to accommodate the conduit or piping. The presence of numerous metal parts, sections, panels, or other reinforcing members can substantially interfere with that procedure and may require the use of additional insulating parts between the piping and conduit and any metal parts in the conduit or piping.
In some applications, siding or other outer surface treatments are added to the above ground wall sections formed with ICF systems. Such surface treatments typically use conventional siding or paneling materials designed for installation on conventional wooden frames along conventionally spaced attachment points. Many ICF systems also lack continuous or semi-continuous attachment points along the full height of the wall and corner structures permitting the fastening of materials, paneling, siding or other material to the structures. Such systems further lack integral structures providing a drainage plane or rain screen behind such surface treatments to permit the flow or other movement of water penetrating siding or other surface treatments out from behind the siding.
As a result, in many ICF systems extra attachment systems of wood or other materials must be added to the exterior wall of ICF systems to permit the installation of such surface treatments on the ICF system, as well as for use alone or in conjunction with other rain screen materials, to provide a drainage plane behind the surface treatment. These additional construction steps also will increase the cost and difficulty of use of such ICF systems.
In most forming systems, conventional and ICF, window and door frames or xe2x80x9cbucksxe2x80x9d must be mounted in the forms to provide a frame for installing the windows or doors in the formed concrete structure. Such window or door bucks commonly are custom fabricated on-site during the assembly of the system, and, thus the resulting bucks are non-standard sizes or fail to conform to the dimensions of the window or door that is to be installed in the buck.
As a result, considerable time and effort may be required to fit and adjust the windows or doors and the corresponding bucks to ensure the proper installation of the windows and doors in the formed structure. Thus, it was difficult and in most instances impractical to achieve construction efficiencies and cost reductions that can be obtained with prefabricated parts and to increase the efficiency of the on-site construction procedures resulting in increased costs and labor expenses in using such systems.
Similarly, most forming systems are installed on a base of a concrete footing or other level base which often is uneven and irregular and require time consuming shimming procedures to properly level the forming system. The surfaces adjacent to the footing also typically are unfinished and may be unstable dirt, clay, mud or other such surfaces. A concrete floor or slab may later be poured over those adjacent surfaces, but usually not until after the walls are constructed. In prior systems, there has been little, if any, attention given to the possibility of preforming floors or other surfaces adjacent to the footing to provide improved and stabilized work surfaces adjacent to a wall forming system prior to pouring the wall structures.
For at least the above reasons, there is a need for improved forming systems utilizing insulating foam forms that are adaptable for use with standard construction techniques similar to conventional forming systems, and specifically those using vertically oriented forms similar to the conventional wood and metal forms. There further is a need for xe2x80x9copenxe2x80x9d forming systems that utilize standard, preformed low density, insulating foam panels, or rigid panels of other materials such as plastics, polymeric composites, cementitious wood and foam panels, etc. that can be supplied in generally generic, standard shapes and panels dimensions. There also is a need for systems that are readily adaptable for use in circumstances where fire resistance, insect and/or pest resistance, impact resilience, form removability, high energy efficiency, and flexibility to accommodate changes in material availability and cost is important.
In addition, there is a need for a forming system that can be relatively simply adapted at the work site for a variety of shapes and applications, including relatively simple to construct corner assembly and easily adaptable corner assemblies of a variety of corner angles, as well as a variety of curved wall corner shapes. Moreover, there is a need for a forming system that provides a versatile wall construction that can be relatively easily adapted to a variety of post-forming construction and wall treatment techniques. Similarly, there is a need for an improved footing and window systems for such forming systems as well as for other related systems.
The invention provides an improved system for forming foundations, walls, buildings and other structures having one or more walls made of concrete or other pourable, hardenable materials (together referred to herein as xe2x80x9cconcretexe2x80x9d). The system uses substantially rigid forming panels and is xe2x80x9copenxe2x80x9d in that forming panels from a variety of sources can be utilized in the system with limited (if any) changes or alterations to the components used in the system. Such panels particularly include insulating foam panels, and also include substantially rigid panels of wood, plastic, polymeric composites, cementitious composites of foam, fibers, metals etc. and other such materials, many of which provide additional insulating properties.
The system in an important aspect provides wall tie rail and corner tie rail components that are adaptable for use in a variety of construction applications using forming procedures and techniques readily adaptable from conventional forming system construction and assembly procedures. The tie rails and corner rails may be used to form a wide variety of wall and corner shapes that substantially reduce the need for specialized corner components and extensive bracing such as that required in prior systems. The tie rails also may be made of a variety of materials to provide properties such as reduced weight and cost, and/or fire and insect resistance. The choice of the tie rail materials, in addition, in most instances, may be made without regard to the panel materials.
The forming system of the invention, in addition, is relatively easily adapted to provide corners with a variety of angles and curved corner and wall sections. The system also provides exterior components that are adaptable for use with a variety of wall treatments, providing drainage planes beneath such treatments, and providing readily accessible and predictable attachment locations for wall and surface treatments, appliances etc. that may be applied to the surfaces of the completed structure.
The forming system of the invention further provides improved footing systems, and window and door construction components that provide for substantial improvements in construction efficiencies. The forming system of the invention, in addition, minimizes the number of specialized forms and forming equipment necessary for the variety of applications suitable for the systems.
In one aspect, the invention provides a system of low density, expanded foam panels with relatively high insulating properties to provide forming systems for concrete walls and corners of a variety of dimension and shapes, including without limitation standard wall and corner configurations, angled walls and corners, and curved walls and corners. The forming systems may employ generally available insulating foam panels, or panels of other materials, having standard dimensions and thicknesses, and such panels need not possess specially designed slots, grooves, lap joints or the like.
Such foam panels may be provided especially for use in the system of the invention, or may be of a generic construction that is utilized in other insulating applications. Such panels, and the above mentioned panels of other materials, typically are of dimensions familiar to contractors and others responsible for assembling forming systems, typically have a dimensional consistency that provides substantial efficiencies in manufacturing and use that reduce the costs associated with the panels, can be selected to provide a variety of properties and potential applications, frequently do not require additional engineering or specialized knowledge to use, and provide a consistency in dimensions and structural elements of the completed structure that often is not present in other systems.
In one aspect of the invention, insulating foam panels are provided as generally vertical panels that are assembled in a configuration and using procedures similar to conventional concrete forms. In this system, one or more of pairs of generally vertical panels are positioned so that the panels are spaced a predetermined distance apart to provide a forming cavity to receive concrete materials. The pairs of panels are positioned adjacent to other panels of a similar orientation to form a generally continuous inner wall defined by one set of panels and an outer wall defined by the other opposing set of panels and forming a cavity sized to form a concrete wall structure (or multiple walls) with a predetermined thickness, height and length.
The wall panels are positioned and maintained in the proper alignment by a series of wall tie rails disposed between the adjacent wall panels that tie together and reinforce the opposing sets of wall panels. The wall tie rails assist in resisting the displacement of the panels from their proper position due to pressures and forces imposed on the panels during the filling of the forming cavity with concrete, the working of the concrete between the forms and the curing of the concrete, as well as incidental stress encountered during assembly of the system.
Each of the wall tie rails is provided with a first retaining section disposed between the adjacent outer wall panels that engages and holds the vertical edges or borders of the wall panels. The first section generally extends along a substantial length of the vertical edges of the adjacent panels, and in one aspect along substantially all of the length of the vertical edges of the panels. The wall tie rails similarly include a second retaining section disposed between the adjacent inner wall panels that engages and holds the surfaces of each of the inner wall sections, and also extends generally along a substantially the length of (and one aspect along substantially all of) the vertical edges of the adjacent inner panels. The wall tie rails further include at least one web section extending and joining the first retaining section to the second retaining section.
The wall tie retaining sections hold the edges of the wall panels in a channel defined by exterior and an interior flange, spaced apart a distance effective to allow for the insertion of the panel edges in the channel. The flanges hold the panel edges, and, in one aspect, this is a functional engagement enhanced by locking ridges, adhesives or other engagement elements on the surfaces of the flanges defining the interior of the channels. In one aspect, the spacing of the flanges permits the placement of the panel edges into the channels using relatively low insertion force. The combination of inner and outer retaining sections and the connecting webs cooperate to maintain the foam wall panels in the proper orientation and relative position.
The flanges of the retaining sections, in addition, extend over the panel surfaces a distance effective with the engagement of the panel edges in the above mentioned channels to restrain the outward movement of the panels when the forming cavity is filled with concrete, and which the concrete is subsequently worked within the system and cured. The wall ties, in addition, generally seal and prevent or limit the leakage of concrete through the joints between the wall during such operation.
The system also provides, where necessary, corner assemblies defined by the intersection of at least two outer wall panels at a preselected angle and the intersection of at least two inner panels at a preselected angle, together defining a corner forming cavity. In this aspect of the invention, the corner panels and adjacent wall panels are of the same general configuration as the wall panels and are positioned at a predetermined angle by a corner tie assembly. The corner tie assemblies provide corner tie rails, and inner and outer brackets located at the angular intersection of the inner and outer corner panels, respectively.
The corner tie rails include outer retaining sections that, in one aspect, hold the vertical edges of the corner panels, generally along a substantial length of the vertical panel edges in a manner similar to that described above for the wall tie rails. The corner tie rails further include webs with a connecting end extending between the outer retaining section and the inner corner bracket. The webs may be removable from a corner bracket with a web end that is insertable into tie channels on one of the corner brackets.
One or more webs also extend from the outer corner bracket to the inner corner bracket, which generally is the greatest distance between the form (i.e., between the intersections of corner inner panels and the outer corner panels). These webs also may be removable from the corner bracket as discussed above for the corner tie rails.
The retaining sections of the corner brackets include walls defining engagement channels sized to accept and hold the vertical edge of the corner panels, in much the same manner as the above referenced wall tie rail retaining section. These channels are disposed in an angular disposition that is generally the same as the angular disposition of the corner panels.
The corner tie rails and corner brackets that cooperate to maintain the panels in the correct orientation and position during the assembly of the system. The corner tie rail retaining section and webs, further cooperate to form a self-reinforcing system that resists the displacement of the corner panels from their relative alignment and position by the outward forces exerted on the panels by the pouring, working and curing of the installed concrete between the corner forms, and do so where those forces may exceed the forces expected on other aspects of the system as a result of the geometry of the corner forms and forming cavity.
In yet another aspect of the invention, the wall and corner tie rails are made of a polymeric material or a metal that is relatively easily molded or formed. The corner tie rails may include a web with one or more ends that may be disengaged from the inner corner bracket so that the rails and corner system may be collapsed for easy shipping and storage.
In another aspect of the wall and corner tie rails of the system, a line of weakness is incorporated in retaining sections that permits the detachment of the exterior flanges of the first or outer retaining section from the completed, cured wall or corner section. This provides a relatively consistent surface on the exterior surfaces of the forming panels that is adaptable for wall treatments of stucco, plaster or other such treatments best applied to such flat or planar surfaces. The removable aspect of the retaining sections, in addition, allows for the selective removal of one or more panels from the completed, cured structure to expose the surface of formed concrete wall or corner.
Alternatively, the exterior flanges of the wall and corner ties and the corner brackets are used as attachment parts for shelving, plumbing exterior conduit, and wall treatments requiring the use of securement points. The regular, vertical arrangement without interruption of the exterior flanges of the wall ties is particularly useful in the installation of siding or paneling materials. In another aspect, the wall and corner tie rails and corner brackets are rails of a light weight metal to improve the system""s fire and pest resistance, and to provide improved attachment points on the exterior of the system. In another aspect, these flanges on the external surface of the forms also may provide channels or drainage planes behind siding and other surface treatments without the need for additional spacers, boards, furring strips and the like.
In one aspect of the system of the invention, the system can be adapted to form wall sections and corner sections of a variety of different thicknesses. In that aspect, the wall tie rail webs are provided with a width corresponding to the desired wall thickness. The inner corner bracket of the corner assembly is adapted to provide multiple channels to webs of variable widths extending from the outer corner bracket having widths corresponding to the desired wall thickness, and to allow the adjustment of the size of the corner forming cavity without changing the corner bracket assemblies.
In another aspect, the corner brackets are provided with channels having a common hinged corner and opposing freely movable corners. As a result, the channels and corner panels can be positioned at a wide range of corner angles by pivoting the channels around the hinged corner. The corner channels also may be locked in place by locking plates fixed over the freely movable corners of the brackets.
In yet another aspect, curved corners or walls may be formed using the wall tie rails and panels of the system. In one such aspect, slots or recesses are formed or cut in one or more in the surfaces of the foam panels so that they can be curved by arching the panels in the desired direction of curvature. Opposing pairs of such curved panels with corresponding curvature may be positioned and held in place by adhesives and the above mentioned wall tie rails to form the desired curved forming cavity without the need for specialized forming devices or apparatus.
In another aspect of the invention, the forming system includes a footing bracket system that engages the bottom edges of the wall panels to support and retain the panels in their proper position. The footing includes a first and second generally xe2x80x9cLxe2x80x9d shaped footing bracket spaced apart a distance sufficient to accommodate the above mentioned and corner assemblies, and the desired forming cavity between the brackets. Each bracket may be provided with drainage channels, and, in one aspect, may include a base plate extending towards the other bracket to provide a generally level base for the wall and corner assemblies.
The vertical segment of the xe2x80x9cLxe2x80x9d shaped brackets also may extend upward a distance effective to serve as an outer form for concrete slabs, floors, walkways and similar structures adjacent the forming system. This provides the capability for forming such prepared structures before assembly of the wall and corner forms to provide stable, prepared work surfaces to efficiently install the wall and corner forming systems.
Another aspect of the system of the invention provides supporting channels or base plates for use in utilizing the system to construct multi-level or storied structures. Such channels and base plates may be installed along the upper borders of the wall and corner forms of the system in a previously installed system. After the base system is filled with concrete, and the concrete is at least partially cured, a second system is then installed on and above the first system using the base plates to locate and reinforce the bottom borders of the second system in a manner similar to the above mentioned footing brackets. The base plates also assist in resisting leakage of the concrete poured to form the second wall structure formed by the panel system with the panel forms of the second system installed in the channels formed on the upper border of the first system.
In another aspect of the forming system of the invention, preformed window or door bucks that are matched to preconstructed windows or doors are provided. The bucks are installed in the forming system of the invention to provide attachment frames for the matching windows and doors.